Projection microscope

ABSTRACT

A stereoscopic microscope having an illuminator disposed in one optical path and a projection lens and screen in the other. The illuminator provides light through one optical path to the object plane, from which it reflects along the other optical path. The projection lens projects a greatly magnified image onto the screen for viewing without conventional eyepieces.

United States Patent lnventor John Balan Chirayath Amherst, N.Y. Appl.No. 830,639 Filed June 5, 1969 Patented Mar. 30, 1971 Assignee AmericanOptical Corporation Southbridge, Mass.

PROJECTION MICROSCOPE 1 Claim, 4 Drawing Figs.

U.S. Cl 350/9, 350/18, 350/34, 350/91, 353/39 Int. Cl G02b 21/22, G02b21/36 Field of Search 350/9, 18,

[56] References Cited UNITED STATES PATENTS 1,920,183 8/1933 Bossing353/39 2,209,532 7/1940 Michel 350/9 2,363,388 11/1944 Boughton etal.... 353/39XA 2,578,013 12/1951 Monk 350/34 Primary Examiner-David H.Rubin Attorneys-William C. Nealon, Noble S. Williams and Robert J. BirdABSTRACT: A stereoscopic microscope having an illuminator disposed inone optical path and a projection lens and screen in the other. Theilluminator provides light through one optical path to the object plane,from which it reflects along the other optical path. The projection lensprojects a greatly magnified image onto the screen for viewing withoutconventional eyepieces.

PATENTED man 1971 SHEET 1 SF 3 INVENTOR. ITOHN B. CHIRAYATH ATTORNEYPATENTEMARBOIQ?! 3572.884

SHEET 2 [1F 3 INVENTOR.

JOHN B CHIRAYATH BY MM? AT TOPNEY BACKGROUND OF THEINVENTION The presentinvention is related to microscopes in general and, in particular, to amicroscope being adapted to have a projection lens and projection screenas an alternative to a conventional eyepiece, for ease in viewing theimage.

Projection microscopes are known in the prior art. They generally arespecial purpose instruments providing an image which can be seen only ona projection screen.

It is an object of the present invention to provide a stereoscopicmicroscope which is adaptable for use with eyepieces or a projectionscreen.

Another object is to provide a projection microscope avoiding the use ofbeam splitters in order to maximize the light transmitted to theprojection screen.

Other objects, advantages, and features will become apparent from thefollowing description of one embodiment thereof when taken in connectionwith the accompanying drawing.

SUMMARY OF THE INVENTION Briefly, the present invention is practiced inone form by a stereoscopic microscope adapted to accommodate anilluminator in one optical path (the light path). Light from theilluminator is directed through this optical path to the object and isreflected therefrom through the other optical path. A projection lens isincluded in addition to a conventional eyepiece in the other opticalpath (the projection path) and a mirror is movable in the projectionpath to render the microscope alternatively a conventional or aprojection microscope. A projection screen is positioned relative to theprojection lens.

DRAWINGS In the drawing:

FIG. 1 is a perspective view of a stereoscopic microscope including myinvention and with conventional eyepieces;

FIG. 2 is a perspective view of a stereoscopic microscope including myinvention and in which the eyepieces are replaced by an illuminator;

FIG. 3 is a perspective view of an adapter portion of the apparatusshown in FIGS. I and 2; and

FIG. 4 is a schematic view of the optical system of the stereoscopicmicroscope shown in FIG. 2.

DESCRIPTION Referring now to FIG. 1, a stereo microscope is generallyindicated at 2 and includes an objective 4, a rotatable turret 6, and apair of twin eyepieces 8, all of which members are mounted relative aframe, generally indicated at 10. Such a microscope by itself is knownto the prior art and is described in detail in U.S. Pat. No. 2,90 l,943, issued to Robert B. Tackaberry. In addition to such a microscope,the present apparatus includes an adapter member 14.

Referring now to FIG. 2, in general the same microscope 2, objective 4,rotatable turret 6, adapter 14, and frame are shown. In the place ofeyepieces 8 and their associated housing 12, an illuminator 16 ismounted relative to the adapter 14. A projection screen 18 is mountedrelative to adapter 14 in both the FIG. 1 and FIG. 2 configurations.

In FIG. 3, a projector adapter 14 is shown individually. It includes twooptical path apertures 20 and 21 which correspond to the optical pathsof the microscope and which, in the projection microscope, form a partof light path 22 and projection path 24. A mirror 26 is disposed inprojection path 24 and is pivotally mounted on a spindle 40 whichextends through the body of adapter 14 for external control. By use ofspindle 40,

mirror 26 can be swung into alternate positions. Adapter I4 furtherincludes a horizontal projection tube 28 and a vertical projection tube30, both such tubes'defining a part of the projzection path 24. Amirror32 is disposed in the pr ection path Pro ection 4 at the juncture of proection tubes 28 and 30 tube 30 includes a projection lens 38 in theprojection path 24. In one of its alternate positions, mirror 26 isswung clear leaving aperture 21 clear, permitting light from the objectto enter the corresponding eyepiece 8 for conventional microscopy. Inits other position, mirror 26 is swung into path 24 to direct light totube 28 and to the screen 18.

FIG. 4 shows schematically the optical elements and optical paths of theprojection microscope of the present invention. The optical system isshown related to an object plane 34 on which is disposed an Object at 26to be examined.

By comparison of FIGS. 1 and 2, it will be appreciated that thedifference between the FIG. 1 use as a conventional microscope and theFIG. 2 use as a projection microscope is simply the removal of housing12 and its associated eyepieces 8 from adapter 14 and the attachment ofilluminator I6 to adapter 14. In connecting illuminator 16, as in FIG.2, a cover plate 42 fits over adapter 14 and covers the aperture 21.

In operation, when lamp 16 is illuminated, light therefrom is directedalong light path 22 through objective 4 and onto ob ject plane 34. Thelight reflects from object plane 34, and from object 36, alongprojection path 24 and through objective 4. Mirrors 26 and 32 directthis light along the projection path 24 to projection lens 38.Projection lens 38 thereupon projects the light and the image of object36 onto viewing screen 18 where it can be seen greatly magnified andwithout the use of conventional eyepieces. By simply tilting mirror 26to its alternate position and replacing the lamp by the eyepiecehousing, the microscope can be used conventionally.

It will be apparent that by means of the present invention a microscopehas been provided which is adaptable for use con ventionally witheyepieces or alternatively as a projection microscope. Furthermore, itwill be appreciated that as a projection microscope, the presentinvention avoids the use of beam splitters and thus maximizes the lighttransmitted to the projection screen.

It may occur to others of ordinary skill in the art to makemodifications of the present invention which will lie within the conceptand scope thereof and will not constitute a departure therefrom.Accordingly, it is intended that the invention be not limited by thedetails in which it has been described, but that it encompass all withinthe purview of the following claims.

Iclaim:

I. In a stereoscopic microscope having objective lens means providingfirst and second optical viewing paths converging at an object plane, abody portion having apertures corresponding to said first and secondoptical viewing paths, and a binocular eyepiece assembly detachablymounted on said body portion with the eyepieces aligned with therespective optical viewing paths; a projection adapter including ahousing detachably mounted between said body portion and said binoculareyepiece assembly, said housing having first and second aperturescorresponding to said first and second optical viewing paths and havinga third aperture intersecting said first housing aperture and defining aprojection light path to a projection screen supported from said housingin offset relationship, a mirror pivotally mounted in said first housingaperture and having a control handle extending externally of saidhousing to selectively direct light to one of the binocular eyepiecesand to the projection screen, and a light source unit for detachablemounting on said housing in alignment with said second housing aperturewhen said binocular eyepiece assembly is removed for illuminating theobject plane through said second optical path.

1. In a stereoscopic microscope having objective lens means providingfirst and second optical viewing paths converging at an object plane, abody portion having apertures corresponding to said first and secondoptical viewing paths, and a binocular eyepiece assembly detachablymounted on said body portion with the eyepieces aligned with therespective optical viewing paths; a projection adapter including ahousing detachably mounted between said body portion and said binoculareyepiece assembly, said housing having first and second aperturescorresponding to said first and second optical viewing paths and havinga third aperture intersecting said first housing aperture and defining aprojection light path to a projection screen supported from said housingin offset relationship, a mirror pivotally mounted in said first housingaperture and having a control handle extending externally oF saidhousing to selectively direct light to one of the binocular eyepiecesand to the projection screen, and a light source unit for detachablemounting on said housing in alignment with said second housing aperturewhen said binocular eyepiece assembly is removed for illuminating theobject plane through said second optical path.